Cholinomimetics recap (FINAL)

Question 1

Cholinoreceptors

Answer 1

1. Muscarinic receptors
   - In heart, GI sm, glands, urinary bladder,
   CNS
   - Sympathetic nerves: certain sweat glands
2. Nicotinic receptors
   - Faster than muscarnic
   - Found in neuromuscular junction,
   Adrenal medulla, chromaffin cells,
   autonomic ganglia
3. Acetylcholine binds to both

Question 2

Direct acting cholinomimetics

Answer 2

Bind to receptor
Choline esters: carbachol
Alkaloids: pilocarpine (opthalmic use)

Question 3

Target of direct acting cholinomimetics

Answer 3

1. GI tract, urinary tract, Cardiovascular system
   Glandular secretion increase
   Gi tract motility increase
   Uterine contraction via muscarinic
   BP decrease
   Bradycardia; negative ino-chromo-dromotropic
   Bronchial contraction
   Miosis
   Urinary bladder contractions

Question 4

Side effects of direct acting cholinomimetics

Answer 4

Colic, diarrhea
Miosis
Vasoconstriction of bronchial vessels
Phlegm retention in respiratory tract
Hypotension, bradycardia
Miscarriage

Question 5

Indirect acting cholinomimetics

Answer 5

Reduce activity of acetylcholinesterase
Cause accumulation of Ach in synaptic cleft
Cause impact to all receptors in organism
Depolarisation of nicotinic receptors
Used to increase peristalsis, induce miosis, antidote to curare-like drugs

Question 6

Antidote to indirectly acting cholinomimetics

Answer 6

Atropine
- Blocks muscarinic receptors

Question 7

Side effect of indirect acting cholinomimetics

Answer 7

Salivation
Diarrhea, colic, vomiting
Tremors, muscle weakness
Shortness of breath
Hypotension, bradycardia
Miosis
Respiratory paralysis

Question 8

Irreversible cholinesterase inhibitors

Answer 8

1. Organophosphorous compounds:
   
   • pesticides, insectisides
2. Enzyme must be synthesised to restore
   function -SLOW!
3. Can cause severe poisoning - all side
   effects as severe versions

Question 9

Precautions with cholinesterase inhibitors

Answer 9

Synergic effect fatal
Some tranquilizers decrease cholinesterase activity
Hepatic disease -> reduced synthesis of cholinesterase

Question 10

Cholinoblockers

Answer 10

1. Antimuscarinic agents
   - Atropine
2. Block parasympathetic nerve impulses
3. Competitive; can be overcome by large doses of Ach or cholinomimetics
4. Nonspecific, but differences in susceptibility in tissues